Stellar Populations and the Star Formation Histories of LSB Galaxies: III. Stellar Population Models
Stellar Populations and the Star Formation Histories of LSB Galaxies: III. Stellar Population Models
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DOI：
10.1017/pasa.2014.32
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发表时间：
2014-07
影响因子：
6.3
通讯作者：
J. Schombert;S. McGaugh
中科院分区：
文献类型：
--
作者：
J. Schombert;S. McGaugh
摘要设计了一系列的星族模型来研究富气体低表面亮度星系的星星形成历史。LSB星系的独特之处在于具有非常蓝的颜色，低Hα发射和高气体分数的特性，这表明了恒定的星星形成历史（与大多数螺旋和不规则星的下降星星形成模型相比）。该模型模拟使用一个不断发展的多金属丰度复合人口，遵循化学富集计划的基础上银河系的观测。颜色和时间敏感的恒星演化分量（即，BHB，TP-AGB和蓝色离散星），模型的颜色扩展到斯皮策波长范围内的新的观察比较。一般来说，LSB星系很好地匹配了恒定的星星形成场景，颜色的变化可以通过在过去的0.5 Gyrs（即，弱爆发）。来自S4 G样本的早期型螺旋更适合下降的星星形成模型，其中星星形成在过去12个回转中减少了40%。
Abstract A series of population models are designed to explore the star formation history of gas-rich, low surface brightness (LSB) galaxies. LSB galaxies are unique in having properties of very blue colors, low Hα emission and high gas fractions that indicated a history of constant star formation (versus the declining star formation models used for most spirals and irregulars). The model simulations use an evolving multi-metallicity composite population that follows a chemical enrichment scheme based on Milky Way observations. Color and time sensitive stellar evolution components (i.e., BHB, TP-AGB and blue straggler stars) are included, and model colors are extended into the Spitzer wavelength regions for comparison to new observations. In general, LSB galaxies are well matched to the constant star formation scenario with the variation in color explained by a fourfold increase/decrease in star formation over the last 0.5 Gyrs (i.e., weak bursts). Early-type spirals, from the S4G sample, are better fit by a declining star formation model where star formation has decreased by 40% in the last 12 Gyrs.